Toggle switches are well known, especially in the electrical arts. These toggle switches typically provide a manually accessible member which has metastability in a first position and a second position. For example, these positions may represent "ON" and "OFF". In many instances, these toggle switches are readily accessible and intended for casual use, for example domestic lighting. Accidental use of the toggle carries a very low penalty, and feedback of the resulting position is immediately apparent. Thus, no interlock or positional retaining means need be provided.
See, e.g., U.S. Design Pat. No. 274,326; U.S. Pat. Nos. 5,744,768; 5,557,082; 5,463,199; 5,361,051; 5,293,016; 5,214,402; 5,162,765; 5,117,208; 5,066,935; 4,528,531; 4,488,133; 4,347,488; 4,024,894; 3,959,755; and 3,863,042.
Some situations provide a substantial penalty for accidental actuation. For example, during repair or installation, accidental actuation may result in electrocution or shock. Therefore, where a worker is not in the immediate vicinity of a switch and is in the process of installation, repair or maintenance, often a lock or flag is placed to alert others that the switch should not be reset or to prevent resetting without significant efforts.
Finally, a number of applications pose a significant penalty for accidental actuation of a switch, but do not require a lockout or obtrusive warning, and do not interfere with normal operation of the switch. For example, in a process control system, inappropriate actuation or deactuation of a control switch may result in scrapping of an entire production lot.
A known toggle switch switch retention system, shown in FIGS., 1A, 1B and 1C, provides a flat spring element adjacent to the toggle which engages a hole in the toggle, thereby preventing actuation without manipulation of the spring element. This flat spring element must be attached to the switch body in order to be effective, and thus requires a modification of the switch itself Further, the manipulation of the spring element is potentially inconvenient.